chore(deps): update registry:2 docker digest to a3d8aaa (#4443)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [registry](https://redirect.github.com/distribution/distribution) |
digest | `319881b` -> `a3d8aaa` |

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internal/dev/docker-compose.registry.yml

@@ -1,5 +1,5 @@
 services:
   registry:
-    image: ${FTL_REGISTRY_IMAGE:-registry:2@sha256:319881be2ee9e345d5837d15842a04268de6a139e23be42654fc7664fc6eaf52}
+    image: ${FTL_REGISTRY_IMAGE:-registry:2@sha256:a3d8aaa63ed8681a604f1dea0aa03f100d5895b6a58ace528858a7b332415373}
     ports:
       -  "${FTL_REGISTRY_PORT:-15000}:5000"